About a year ago I bought the Sennheiser MX 550 earphones for my MP3 player. After using a pair of Sony earphones that came with my Sony Walkman for more than 6 years the right earphone suddenly stopped functioning. It's kinda annoying to only hear the left channel of music so I decided to buy a new pair of headphones. I did some research on the web and decided to go for the Sennheiser MX 550.